Lexical-gustatory synaesthesia is an odd condition, very rare. Its symptoms are such that when the sufferer thinks of a concept, their brain accesses its taste memories, and calls forth the taste of an associated food, as strong as it would be if they were tasting it now.

Synaesthetes tend to experience the same taste for words with similar sounds. In one subject, for instance, not only does the word "mince" call up a mince flavour, but "prince" and "cinema" do too. This suggests that the taste is somehow tied to the sound or the spelling of the word.

Julia Simner at the University of Edinburgh and her colleague, Jamie Ward, at University College London, both in the UK, showed 96 pictures of obscure items such as a gazebo, a geisha or a metronome to six subjects with lexical-gustatory synaesthesia.

In all but one subject they managed to induce a "tip of the tongue" condition, where the person recognised the object but could not remember what it was called, what letter its name started with or how many syllables the elusive word had. The researchers found that these individuals could still identify what taste the item elicited. One woman, for instance, unable to come up with the word "gramophone", reported tasting Dutch chocolate, and precisely the flavour that the word is associated with for her.

This shows that it is the meaning of the word ? not the sound or spelling ? that elicits the taste sensation in these people, Simner says. She suspects the associations begin in childhood.

This work has consequences far beyond the realm of the condition of lexical-gustatory synaesthesia, of course. It shows that it is perfectly possible to stimulate electrical pathways in the brain, which result in the exact replication of previously tasted flavours.

For the VR replication of the sense of taste, the proof that the concept is even possible that this study shows, is certainly a profound development.

Further research into the condition lexical-gustatory synaesthesia, or any synaesthesia, will be of direct benefit to virtual reality applications, as further understanding of how these concept linkings operate, can only be beneficial to us.